US20170030382A1 - Combination Device for Lockout and Partial Stroke Test of Valve Actuators - Google Patents
Combination Device for Lockout and Partial Stroke Test of Valve Actuators Download PDFInfo
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- US20170030382A1 US20170030382A1 US15/225,515 US201615225515A US2017030382A1 US 20170030382 A1 US20170030382 A1 US 20170030382A1 US 201615225515 A US201615225515 A US 201615225515A US 2017030382 A1 US2017030382 A1 US 2017030382A1
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- housing
- extension rod
- actuator
- nut
- sleeve
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
- F15B15/26—Locking mechanisms
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
- F16K31/16—Actuating devices; Operating means; Releasing devices actuated by fluid with a mechanism, other than pulling-or pushing-rod, between fluid motor and closure member
- F16K31/163—Actuating devices; Operating means; Releasing devices actuated by fluid with a mechanism, other than pulling-or pushing-rod, between fluid motor and closure member the fluid acting on a piston
- F16K31/1635—Actuating devices; Operating means; Releasing devices actuated by fluid with a mechanism, other than pulling-or pushing-rod, between fluid motor and closure member the fluid acting on a piston for rotating valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
- F15B15/24—Other details, e.g. assembly with regulating devices for restricting the stroke
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
- F15B15/26—Locking mechanisms
- F15B15/261—Locking mechanisms using positive interengagement, e.g. balls and grooves, for locking in the end positions
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
- F15B19/002—Calibrating
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K1/00—Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces
- F16K1/32—Details
- F16K1/50—Preventing rotation of valve members
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K1/00—Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces
- F16K1/32—Details
- F16K1/52—Means for additional adjustment of the rate of flow
- F16K1/523—Means for additional adjustment of the rate of flow for limiting the maximum flow rate, using a stop
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K35/00—Means to prevent accidental or unauthorised actuation
- F16K35/02—Means to prevent accidental or unauthorised actuation to be locked or disconnected by means of a pushing or pulling action
- F16K35/022—Means to prevent accidental or unauthorised actuation to be locked or disconnected by means of a pushing or pulling action the locking mechanism being actuated by a separate actuating element
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K35/00—Means to prevent accidental or unauthorised actuation
- F16K35/02—Means to prevent accidental or unauthorised actuation to be locked or disconnected by means of a pushing or pulling action
- F16K35/022—Means to prevent accidental or unauthorised actuation to be locked or disconnected by means of a pushing or pulling action the locking mechanism being actuated by a separate actuating element
- F16K35/025—Means to prevent accidental or unauthorised actuation to be locked or disconnected by means of a pushing or pulling action the locking mechanism being actuated by a separate actuating element said actuating element being operated manually (e.g. a push-button located in the valve actuator)
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K35/00—Means to prevent accidental or unauthorised actuation
- F16K35/06—Means to prevent accidental or unauthorised actuation using a removable actuating or locking member, e.g. a key
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/02—Mechanical layout characterised by the means for converting the movement of the fluid-actuated element into movement of the finally-operated member
- F15B15/06—Mechanical layout characterised by the means for converting the movement of the fluid-actuated element into movement of the finally-operated member for mechanically converting rectilinear movement into non- rectilinear movement
- F15B15/066—Mechanical layout characterised by the means for converting the movement of the fluid-actuated element into movement of the finally-operated member for mechanically converting rectilinear movement into non- rectilinear movement the motor being of the scotch yoke type
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
- F15B15/26—Locking mechanisms
- F15B2015/267—Manual locking or release
Definitions
- the disclosure relates to the field of lockout devices for preventing the operation of a valve actuator and to the field of valve partial stroke test devices, which permit only a pre-determined extent of motion for the valve actuator.
- ESD valves emergency shutdown valves
- blow off valves blow off valves
- bypass valves bypass valves to prevent pressure build up in upstream or downstream sections.
- ESD valves emergency shutdown valves
- blow off valves blow off valves
- bypass valves bypass valves to prevent pressure build up in upstream or downstream sections.
- Actuation on ESD valves use fail-close actuator that is biased to close the valve, which is normally maintained in an open position by pneumatic pressure.
- These valves automatically close by the spring action or by reserve pneumatic supply upon loss of line air pressure due to a pressure system failure or in response to an emergency shutdown command signal. Regulations mandate periodic testing of such safety-instrumented systems to ensure the valve and all control elements are fully operational in an emergency.
- Partial stroke testing (hereinafter, also “PST”) devices fulfill this testing requirement without having to shut down the valve fully, which may disrupt or be detrimental to the normal process.
- a typical PST device is sandwiched between the valve and the actuator with a mechanical stop engaged to permit only a partial rotary motion of the valve operating member, or has a mechanical stop inserted into the translatory (meaning of, relating to, or involving uniform motion in one direction) path of the pneumatic actuator's piston rod, permitting only partial linear stroke.
- FIG. A Some examples of prior art on lockout and partial stroke valve test apparatus are shown in FIG. A, FIG. B and FIG. C.
- FIG. A shows a typical mechanical device that is fitted between the actuator and a rotary valve, the coupler shaft connects the valve's stem to the actuator's drive element.
- Rotary motion of the valve's drive member is restrained completely by a stopper bolt engaged in the device housing and the end of the stopper bolt locates into a hole or recess in the coupler shaft to lockout the rotary motion of the coupler and thereby the actuator and the valve.
- the device may further be locked out by engaging a lock pin through the housing and the stopper bolt and a padlock engaged into the lock pin.
- FIG. B shows an arrangement to engage a stopper pin in the path of the actuator's piston rod or its extension thereof, to restrict the linear motion of the piston rod in a partial stroke valve test device.
- the spring return stroke is restricted to a small predetermined extent when the stopper pin is inserted in the device's housing, as the end face of the piston rod contacts the stopper pin after the partial stroke and is mechanically restrained by the pin from further motion.
- FIG. C shows a partial stroke valve test device that is fitted between a rotary valve and the actuator with the device's coupler shaft adapted to connect the valve's stem to the actuator's drive member.
- the device typically has this coupler shaft keyed to a rotary member, segmented to provide a radial planar surface that bears on a cam stopper which when engaged, blocks the rotary motion of the segment and thereby the actuator and valve.
- the two extreme positions of the cam shaft select between the operation or test modes of the device.
- the present disclosure relates to embodiments for a reliable and rugged mechanical device which when adapted to a fluid powered valve actuator, performs dual functions of a lockout and a partial stroke test device, capable of withstanding the full force of the pneumatic actuator. Configured as a lockout device, it prevents a pneumatic cylinder actuator's linear motion when the cylinder is pressurized.
- This disclosure pertains to the mechanisms on an exemplary embodiment of a single mechanical device that combines the functionality of a lockout device which prevents a valve pneumatic actuator from operating by fluid power in one mode and as a partial stroke valve test device in the other mode, which permits only a pre-determined extent of actuator's motion.
- the partial stroke test device finds most common use in testing for the anticipated response of the controls on a valve actuator in a fault insertion test. Such a device shall permit only a small movement of the valve stem so as not to adversely affect the pipeline flow and process parameters. This disclosure makes such a device easily field-configurable to a double as a lockout device too, that prevents motion of the actuator when so called for during maintenance.
- the device has an activation mechanism to prevent linear motion of the actuator's piston rod and is set to lock the actuator and thereby the valve is locked in an open or closed position, normally at the stroke end. This can be further locked out in either position with a padlock to ensure the actuator on the process valve is not operated inadvertently or by unauthorized personnel.
- the mechanism enables easy field adjustment, which permits the actuator a pre-determined stroking before blocking further movement.
- the activation mechanism has further options of local operation by a manual lever or by a small short stroke pneumatic cylinder, for remote operation.
- One example of a lockout device in accordance with the present disclosure includes the device housing, two slides with linkages and pins, an actuating plunger, housing cover and an extension rod with an adjustable stopper nut.
- the extension rod is threaded at one end, which engages into one side of the actuator's guide block that is fixedly connected to the piston rod on its other side, integrating the extension rod coaxially with the pneumatic cylinder's piston rod.
- the other end of the extension rod is stepped down and threaded till its end beyond the step.
- An adjustable thimble nut is threaded on this end, forming a groove between the extension rod's step face and the nut's inner face.
- the housing has two slides of thickness adapted to slide into the groove so formed by the extension rod's step and the thimble nut's faces.
- the two slides bear on the device housing on their rear face and their front faces bear on the actuating links and the housing cover. They move towards each other in the activated position or away from each other in de-activated position. This synchronized activating motion of these slides is accomplished by the linear movement of a plunger that is linked in an identical manner to each of these two slides through links and pinned joints.
- the sliding members have semi-circular cut-outs machined on their mating faces which envelope the step on the extension rod when the two slides are moved inwards into the locking position, by pulling outwards on the actuating plunger.
- the axial movement of the extension rod is constrained by the two slides that envelope the step and create an annular surface that the thimble nut bears on.
- the slides bear on the device housing and the thimble nut threaded on the extension rod bears on the slides, thereby blocking axial movement of the extension rod. Since the extension rod is coupled to the piston rod through a guide block in the actuator, the linear movement of the piston rod too is prevented and the actuator is locked out.
- this example of a lockout device in accordance with the present disclosure may be used to lock the pneumatic cylinder actuator in one of such several possible positions.
- the slides move away from each other and their profile clears the boundary of the extension rod and the adjusting thimble nut, thereby letting the extension rod with the thimble nut slide freely through the device housing.
- the same exemplary device configured as a partial stroke valve testing device has the thimble nut backed off on the extension rod threads to create a wide groove between the extension rod step face and the thimble nut inside face.
- the actuation of the plunger outwards from the device housing to effect the synchronized movement of the slides towards each other to engage the test mode or outwards to disengage the test mode remains the same as in the case of the lockout configuration of the device.
- the extension rod can move axially under the influence of the pressure applied to the pneumatic cylinder of the actuator, to the extent of the width of the groove so formed by manual adjustment of the thimble nut.
- the stroke of the piston rod is now permitted for only the width of this groove thus providing an arrangement for partial stroking of the actuator.
- the plunger's position is further secured at its' two end positions by the provision of a safety stop to prevent inadvertent engagement of the operational and testing positions.
- a spring biased pin radially engages a collared nut threaded on the plunger, thereby preventing the plunger's movement unless the safety stop pin is selectively disengaged for the movement of the plunger for the test position or the operational position.
- a manual lever with linkages to operate the plunger is provided to effect the plunger movement effortlessly.
- a variant of this exemplary device to operate the lockout or the partial stroke test functionality by remote operation has the manual lever replaced by a small pneumatic cylinder that is adapted to fit and be coupled to the plunger.
- the device operation is effected by remote signal to a solenoid valve that pneumatically operates this actuation cylinder, which in turn moves the plunger in or out to accomplish the lock-unlock functions.
- a feedback sensor adapted to the mounting of the cylinder returns the confirmation signal of the device's position to the central control unit for further processing and sequencing.
- Another exemplary lockout device in accordance with the present disclosure includes the device housing, indexable sleeve with a double D profiled bore, an actuating lever, housing cover and an extension rod with an adjustable stop nut having a double D profile.
- the extension rod is threaded at one end suited to engage into one side of the actuator's guide block that is fixedly connected to the piston rod on its other side, integrating the extension rod coaxially with the pneumatic cylinder's piston rod.
- the other end of the extension rod is threaded for the required adjustment length and suited to a double D profiled adjustment nut.
- the index sleeve has a double D profiled bore of the same profile as the profiled adjustable stop nut, but only of slightly bigger dimensions so as to just let the adjustment nut slide through the profiled bore, unhindered.
- the two flat faces of the profiled nut are set coplanar to the flat faces in the index sleeve's profiled bore, for the normal operation (full stroke of the actuator).
- the index sleeve can be rotated in the device housing but restricted to only 90 degree rotation by a spring biased plunger pin that indexes into either of the two slots machined radially and 90 degrees apart on the flange of the index sleeve.
- the indexation of the index sleeve from disengaged to the engaged position of the device is accomplished by turning on the hand lever that is fixedly attached to the outer end of index sleeve.
- the sleeve's double D bore profile gets offset to the adjustment nut's profile and this counter posed position prevents the adjustable stop nut from sliding through it.
- the axial movement of the extension rod is constrained by the adjustment nut face bearing on the end face of the index sleeve. Since the extension rod is coupled to the piston rod through a guide block in the actuator, the linear movement of the piston rod too is prevented and the actuator is locked out.
- this exemplary lockout device in accordance with the present disclosure may be used to lock the pneumatic cylinder actuator in one of such several possible positions.
- the sleeve's profiled bore comes back into alignment with the adjustment nut profile, thereby letting the adjustment nut and extension rod slide freely through the sleeve and device housing.
- the same exemplary device when configured as a valve partial stroke testing device has the profiled adjustment nut backed off on the extension rod threads to create a gap between the index sleeve's outer face and the profiled adjustment nut's inside face.
- the actuation of a hand lever to effect the clockwise rotation of the index sleeve to engage the test mode or counter clockwise to disengage the test mode remains the same as in the case of the lockout configuration of the device.
- the extension rod can move axially under the influence of the pressure applied to the pneumatic cylinder of the actuator, to the extent of the width of the gap so formed by manual adjustment of the adjustable stop nut.
- the stroke of the piston rod is now permitted for only the width of this gap thus providing an arrangement for partial stroking of the actuator.
- the hand lever's travel is limited to its' two end positions by the provision of safety stops on the housing cover, to prevent over travel of the index sleeve while effecting device engagement or disengagement for the testing or operational positions, respectively.
- a spring biased pin radially engages in the index slots on the index sleeve's flange, to enable accurate positioning of the index sleeve in its two end positions and to prevent any inadvertent operation of the hand lever.
- the index sleeve is locked in its end positions, unless the safety spring biased plunger pin is selectively disengaged for the rotation of the index sleeve for either of the test position or the operational positions.
- a hand lever to operate the device is provided to effortlessly effect the 90-degree rotation of the index sleeve.
- a provision is also made to positively lock this hand lever in its two extreme positions so determined by the safety stops on the housing cover, with a padlock to prevent unauthorized operation of the device.
- FIG. A shows an exploded perspective view of a prior art coupling of an actuator and a rotary valve.
- FIG. B shows a prior art partial stroke valve test device.
- FIG. C shows a perspective view of a prior art partial stroke valve test device.
- FIG. 1 shows a perspective view of an exemplary valve actuator fitted with the said combination device.
- FIG. 2 shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in unlocked position.
- FIG. 3 shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in locked position.
- FIG. 4 is the section view of an exemplary embodiment of the actuator and combination device mounted on a valve actuator, configured as a partial stroke valve testing device in a disengaged or operational position.
- FIG. 5 is the section view of an exemplary embodiment of the actuator and combination device mounted on a valve actuator, configured as a partial stroke valve testing device in an engaged or testing position.
- FIG. 6 shows a section view of an exemplary embodiment of the fitment of the extension rod of the device on to the guide block of the pneumatic actuator.
- FIG. 7 shows the section view of an exemplary embodiment of the device housing and the locking elements engaged into the extension rod in locked out position.
- FIG. 8 is the sectional perspective view of an exemplary embodiment of the device with the cover removed, showing the slides and linkages housed inside the device housing and the operating lever linked to the plunger that activates the slides movement.
- FIG. 9 shows the section view of an exemplary embodiment of the device housing with cover and the spring biased pin retaining the collar nut and thereby the plunger, in its indexed position.
- FIG. 10 is the perspective view of an exemplary embodiment of the device with the actuating handle locked with a padlock to prevent inadvertent or unauthorized operation of the device.
- FIG. 11 is the elevation view of an exemplary embodiment of the device without the cover showing the positions of the slides and links within the housing, in its unlocked position.
- FIG. 12 is the elevation view of an exemplary embodiment of the device without the cover showing the positions of the slides and links within the housing, in its locked position.
- FIG. 13 is the section view of an exemplary embodiment of the device set to partial stroke valve testing mode by the positioning of the thimble nut and engaging of the slides to permit a predetermined linear movement of the extension rod.
- FIG. 14 shows an exemplary embodiment of the adaptation of the device to remote operation, by replacement of the handle operating mechanism with a short stroke pneumatic cylinder operated by a solenoid valve.
- FIG. 15A shows a perspective view of a valve spring return actuator fitted with another exemplary combination device.
- FIG. 15B shows a perspective view of a valve direct acting actuator fitted with an exemplary combination device.
- FIG. 15C shows a section view of a valve actuator fitted with an exemplary combination device.
- FIG. 16A shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator at one end of the actuator's travel, configured as a lockout device in unlocked position.
- FIG. 16B shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator at mid position of actuator's travel, configured as a lockout device in unlocked position.
- FIG. 16C shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator at the other end of actuator's travel, configured as a lockout device in unlocked position.
- FIG. 16D shows a section view of an exemplary embodiment of the combination device mounted on a variant configuration of a valve actuator at one end of its travel, configured as a partial stroke test device in engaged position.
- FIG. 17A is the section view of an exemplary embodiment of the combination device, configured as a valve partial stroke testing device in a disengaged or operational position.
- FIG. 17B is the section view of an exemplary embodiment of the combination device, configured as a valve partial stroke testing device in engaged or test position.
- FIG. 17C is the part section side view of an exemplary embodiment of the combination device showing the indexed position locking by the spring biased plunger pin, in disengaged position of the device.
- the view also shows the adjustable stop nut profile in alignment with respect to the index sleeve's profiled bore.
- FIG. 17D is the part section side view of an exemplary embodiment of the combination device showing the other indexed position locking by the spring biased plunger pin, in engaged or test position of the device.
- the view also shows the adjustable stop nut profile counter posed with respect to the index sleeve's profiled bore.
- FIG. 17E is an exploded view of an exemplary embodiment of the combination device showing the parts comprising of the device, excluding the extension rod.
- FIG. 17F is an end view taken from FIG. 17A .
- FIG. 17G is an end view taken from FIG. 17B .
- FIG. 18A is the perspective view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in an engaged position at one end of the actuator's end position.
- FIG. 18B is the perspective view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in an engaged position at the other end of the actuator's travel position.
- FIG. 18C is the perspective view of an exemplary embodiment of the combination device with the actuating handle locked with a padlock to prevent inadvertent or unauthorized operation of the device.
- FIG. 19A is the perspective view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device in disengaged position at one end of the actuator's travel position.
- FIG. 19B is the perspective view of an exemplary embodiment of the combination mounted on a valve actuator, configured as a partial stroke test device in the engaged position at one end of the actuator's travel position.
- FIG. 19C is the perspective partial sectioned view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device in disengaged position at the other end of the actuator's travel position.
- FIG. 19D is the perspective partial sectioned view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device showing the set partial stroke.
- FIG. 19E is the perspective partial sectioned view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device in the engaged position at the other end of the actuator's travel position.
- FIGS. 1 through 5 An exemplary embodiment of an actuator 1 of scotch yoke type (e.g., such as a fluid powered cylinder actuator) on which an exemplary embodiment of a lockout and partial stroke test combination device 2 , in accordance with the present disclosure, may be fitted is depicted in FIGS. 1 through 5 .
- the disclosed improvements can be implemented into other types of actuators 1 (by way of example only, and not limited to, linear actuators).
- the exemplary actuator 1 is used for turning the flow control member of a quarter turn valve (not shown).
- the actuator 1 depicted here converts the linear motion of the piston 5 on application of fluid pressure on either side of the piston 5 to rotary motion of the actuator's 1 output drive member or drive element, namely yoke 3 , by the scotch yoke mechanism of this exemplary actuator 1 .
- the actuator 1 could be of rack and pinion style or a diaphragm style and so forth.
- a lockout and partial stroke test combination device 2 in accordance with this disclosure may be used in combination with other cylinder actuator designs than those described herein, for example, on a linear valve actuator (not shown) and may also be used in combination with cylinder actuators (not shown) that are not employed for controlling the flow control member of a valve.
- FIG. 2 and FIG. 3 show the device housing 2 a integrated with the adaptation to (or, adapted to) mount on the actuator housing 1 a to receive and align the device 2 to the axis of the linear motion member 12 of the actuator 1 , namely the cylinder piston rod 4 .
- the extension rod 9 also forms the linear motion member 12 , coaxial to the piston rod 4 , coupled to the guide block 8 of the actuator 1 by threading and in the operation mode, the extension rod 9 freely passes through the lockout and partial stroke test combination device housing 2 a , through the housing bore 2 b , unhindered throughout the entire stroke of the actuator's 1 guide block 8 .
- the rotary motion of the yoke 3 is restrained by the actuator's 1 integral and adjustable travel stops or stop bolt 30 in the actuator 1 .
- the restraining members of the device namely the slides 13 , are in their extreme outward retracted position (as radially retracted away from the linear motion of the extension rod 9 ) and do not impede the motion of the extension rod 9 .
- the extension rod 9 is threaded at one end ( 9 a ) which engages and locks into one side 8 a of the actuator's 1 guide block 8 ; the guide block 8 is also fixedly connected to the piston rod 4 on the other side 8 b of the guide block 8 , integrating the extension rod 9 coaxially with the pneumatic cylinder's piston rod 4 .
- the other end 9 b of the extension rod 9 is stepped down and threaded beyond.
- a thimble nut or fastener 10 is threaded on the other end 9 b of the extension rod 9 for adjustment and positioning, forming a groove (or section of extension rod 9 having an outer diameter less than the outer diameter of the thimble nut 10 ) between the rod's 9 step face 6 and the thimble nut's 10 inner face 7 .
- the slides 13 are housed symmetrically within and guided by planes 18 at the top and bottom in the device housing 2 a to enable them to slide in a unilateral manner by links 17 which are hinged to the slides 13 by pins 16 on one extremity 17 a and to the plunger head 23 on their other extremity 17 b .
- the plunger head 23 is guided in the device housing 2 a and the plunger head 23 is constrained to move only in transverse direction to the slides 13 by the guiding planes 19 of the housing 2 a .
- the slides 13 bear on the recessed face 14 of the device housing 2 a (see FIG. 7 ).
- a housing cover 20 retains the internal parts within the housing 2 a without hindering their motion.
- a tubular cover 44 as shown in FIG. 10 protects the extension rod 9 .
- the extending part 23 a of the plunger 23 from the housing 2 a is threaded to receive an adjustable collar nut 24 which is restrained by a spring biased safety pin or safety device 22 , thread into an adapted extension 21 of the housing cover 20 .
- the extreme end 23 a of the plunger 23 is adapted to receive a pin 29 that engages with the handle 31 forming a hinge 31 a (see FIG. 10 ).
- the handle 31 is pivoted at its end by a pin 28 on a plate link or link plate 27 which in turn is hinged to a fixity 25 on the housing 2 a by a pin 28 a.
- FIG. 3 and FIG. 7 show the device 2 in its lockout configuration and engaged in the locked position.
- the actuator 1 is operated to its' end of travel position, so determined by the adjustable travel stops or stop bolts 30 of the actuator 1 and in the direction that it needs to be locked in.
- the handle 31 is moved to its upper extreme position upon releasing the safety pin 22 by pulling on the pin ring 32 to enable the collar nut 24 and the plunger 23 to traverse outward from the housing 2 a .
- the slides 13 contact each other at their leading faces or ends 34 and close on the stepped down section 9 b of the extension rod 9 with the semi-circular cut-outs 33 forming a hole 33 a encompassing the extension rod's section 9 b between the step face 6 and the thimble nut's inner face 7 .
- Releasing the pin ring 32 returns the safety pin 22 to below the collar 24 and retains the plunger 23 and the handle 31 in this locked position.
- the thimble nut 10 is now so adjusted to let the inner face 7 of the thimble nut 10 just about to bear on the slides' 13 front faces 15 .
- a set screw 11 locks the thimble nut's 10 position on the extension rod 9 .
- a plate link 27 having two holes 36 and 37 that line up with the slot 26 in the extension 31 b of the handle 31 , provide a means of locking the handle 31 against unauthorized operation, in its two said positions by engaging a padlock 35 through the aligned holes 36 or 37 .
- the actuator 1 is operated to its' end of travel position, so determined by the adjustable travel stops 30 of the actuator 1 and to the position that it requires to be tested in for the partial stroke test.
- the handle 31 is operated upward to engage the device 2 into testing mode.
- the thimble nut 10 on the extension rod 9 is loosened and so adjusted that there is a gap 9 c formed between the slides' 13 outer faces 15 and the inner face 7 of the thimble nut 10 .
- the width of this gap 9 c determines the extent of the partial stroke.
- the partial stroke adjustment allows, by way of example only, twenty to thirty ( 20 to 30 ) degrees of rotation of the actuator's 1 output drive member 3 .
- the handle 31 is shifted to extreme down position which translates the slides 13 through the links 17 to retract the slides 13 to their end positions within the housing 2 a , wherein the slides 13 are retracted away from the linear motion member 12 , clearing the thimble nut 10 and the extension rod 9 completely, thereby posing no impedance to the motion of the extension rod 9 .
- a plate link 27 having two holes 36 and 37 that line up with the slot 26 in the extension 31 b of the handle 31 , provide a means of locking the handle 31 against unauthorized operation, in its two said positions by engaging a padlock 35 through the aligned holes 36 or 37 .
- FIG. 14 shows an alternative exemplary embodiment of the device 2 with optional remote actuation, wherein the manual actuation handle 31 and associated parts are replaced by a pneumatic cylinder 42 .
- a pneumatic cylinder 42 is mounted on a bracket 39 that aligns the cylinder 42 coaxially with the plunger 23 and the piston rod 41 of the pneumatic cylinder 42 is coupled to the plunger 23 with a coupler 40 and pin 38 .
- the pneumatic cylinder 42 is operated by a solenoid valve 45 , the power to which is controlled remotely from the central control unit (not illustrated). This arrangement allows the partial stroke valve test to be performed remotely once the device 2 has been configured for the purpose.
- Sensors 43 on the bracket 39 provide a feedback signal to the central control unit for the confirmation of the actuation position, and to further engage or disengage the test mode.
- a scotch yoke type of actuator 101 (e.g., such as a fluid powered cylinder actuator) on which another exemplary embodiment of a lockout and partial stroke test combination device 102 , in accordance with the present disclosure, may be fitted is depicted in FIGS. 15A through 15C .
- the exemplary actuator 101 is used for turning the flow control member of a quarter turn valve (not shown).
- the actuator 101 depicted here converts the linear motion of the piston 105 on application of fluid pressure on either side of the piston 105 to rotary motion of the actuator's 101 output drive member or drive element, namely yoke 103 , by the scotch yoke mechanism of this exemplary actuator 101 .
- the actuator 101 could be of rack and pinion style or a diaphragm style and so forth. It must also be understood that a lockout and partial stroke test combination device 102 in accordance with this disclosure may be used in combination with other cylinder actuator designs than those described herein, for example, on a linear valve actuator (not shown) and may also be used in combination with cylinder actuators (not shown) that are not employed for controlling the flow control member of a valve.
- FIG. 16A and FIG. 16D show the device housing 102 a integrated with the adaptation to (or adapted to) mount on the actuator housing 101 a to receive and align the device 102 to the axis of the linear motion member 112 of the actuator 101 , namely the cylinder piston rod 104 .
- the extension rod 109 also forms the linear motion member 112 , coaxial to the piston rod 104 , coupled to the guide block 108 of the actuator 101 by threading and in the operation mode, the extension rod 109 freely passes through the index sleeve's 106 double D profiled bore 106 e , unhindered throughout the entire stroke of the actuator's 101 guide block 108 .
- the actuator is seen progressively from its clockwise end position to mid travel position and to its counter clockwise end position with the rotary motion of the yoke 103 limited by the actuator's 101 integral and adjustable travel stops or stroke stop bolts 130 in the actuator housing 101 a .
- the extension rod 109 is threaded at one end 109 a which engages and locks into female threads on one side 108 a of the actuator's 101 guide block 108 ; the guide block 108 is also fixedly connected to the piston rod 104 on the other side 108 b of the guide block 108 , integrating the extension rod 109 coaxially with the pneumatic cylinder's piston rod 104 .
- the other end 109 b of the extension rod 109 is threaded to receive a double D profiled adjustable stop nut or fastener 110 on the extension rod 109 for the partial stroke adjustment and positioning.
- the adjustable stop nut 110 too is of a double D profile but is of slightly smaller dimensions than the profiled bore 106 e in the index sleeve 106 , permitting the adjustable stop nut 110 to slide through the index sleeve bore 106 e.
- the stroke restraining member of the device namely the index sleeve 106
- the stroke restraining member of the device is in its extreme counter clockwise position so determined by the spring biased indexing pin 122 locating into the slot 106 j on the index sleeve's 106 flange 106 f .
- the adjustment nut 110 is so set and locked on the extension rod's 109 threads 109 b by a set screws 111 that its double D profile aligns with the index sleeve's 106 double D profiled bore 106 e thereby the motion of the extension rod 109 and the adjustment nut 110 through the index sleeve 106 it is not impeded.
- the index sleeve 106 is located coaxially within the housing 102 a by sliding fit of the index sleeve 106 into the bore 102 b of the housing 102 a .
- the inner face 106 c of the index sleeve flange 106 f bears on the housing's 102 a rear flange face 102 c .
- the housing cover 107 envelopes the index sleeve flange 106 f , with the inner recessed face 107 a of the cover 107 bearing on the index sleeve flange's 106 f outer face 106 d and the cover 107 is bolted on to the housing's 102 a rear flange by bolts 146 .
- the index sleeve is thus free to only rotate within the housing 102 a and the housing cover 107 but constrained from axial movement by the housing end flange face 102 c and the housing cover's 107 inside recessed face 107 a which bear on the two faces of the index sleeve flange's 106 f faces 106 c and 106 d , respectively.
- a housing cover 107 retains the index sleeve 106 within the housing 102 a without hindering the index sleeve's 106 rotary motion within the housing 102 a .
- a tubular cover 144 as shown in FIG. 16E is threaded on the index sleeve's threaded end 106 g to protect the extension rod 109 and the adjustable stop nut 110 .
- a spring biased indexing pin 122 is thread radially into the housing cover 107 and the pin locates into the radial slot 106 j when the device is disengaged and into the slot 106 k when the index sleeve 106 is turned clockwise to engage the device.
- the index sleeve 106 has a threaded hole 106 h that receives the handle 131 that is threaded on its one end and is locked on to the index sleeve 106 by a lock nut 147 .
- FIG. 16D and FIG. 18A show the device 102 in its lockout configuration and engaged to the locked position.
- the actuator 101 Prior to engaging the device, the actuator 101 is operated to its' end of travel position, so determined by the adjustable stop travel stops 130 of the actuator 101 in the direction that it needs to be locked in.
- the device is configured as a locking device when at the actuator's 101 end position, so determined by the actuator's 101 travel stops or stroke stop bolts 130 a or 130 b , the adjustable stop nut 110 is so adjusted on the extension rod threads 109 b to let the inner face 110 a of the adjustable stop nut 110 just about to bear on the index sleeve 106 outer face 106 a .
- the adjustable stop nut 110 is set at this position on the extension rod threads 109 b such that the double D profile of the adjustable stop nut 110 aligns with the index sleeve's 106 double D bore 106 e .
- a set screw 111 locks the adjustable stop nut's 110 position on the extension rod 109 .
- engaging the device so configured as a locking device is effected by operating on the hand lever 131 to rotate the index sleeve 106 to its clockwise extremity upon pulling on the spring biased pin ring 132 to disengage the spring biased pin 122 .
- Application of pressure to the actuator 101 cylinder in the said locked position results in the adjustable stop nut 110 loading on the index sleeve's 106 outer face 106 a , thereby preventing the extension rod 109 , the guide block 108 and in turn the yoke 103 from moving.
- the actuator 101 is thus locked out in this position.
- the spring biased pin 122 is released and handle 131 is shifted to turn the index sleeve 106 counter clockwise to its extremity position determined by the engagement of the spring biased pin 122 into the radial slot 106 j on the index sleeve flange 106 f , to disengage the device whereby the index sleeve's 106 profiled bore 106 e realigns with the double D profiled adjustable stop nut 110 on the extension rod 109 , posing no impedance to the motion of the extension rod 109 through the index sleeve 106 and the housing 102 a.
- the adjustable stop nut's 110 inner face 110 a can now only bear upon the index sleeve's 106 outer face 106 a and cannot go through the index sleeve's double D profiled bore 106 e . This locks up the actuator in its clockwise stroke end position.
- the adjustable stop nut's 110 outer face 110 b can now only bear upon the index sleeve's 106 inner face 106 b and cannot go through the index sleeve's double D profiled bore 106 e . This locks up the actuator in its counter clockwise stroke end position.
- a tab 131 a with a hole on the hand lever 131 lines up with the safety stops 107 b or 107 c with similar hole, providing a means of locking the hand lever 131 in either the engaged or disengaged positions of the device, against unauthorized operation by engaging a padlock 135 through the aligned holes in the safety stops 107 b or 107 c.
- the actuator 101 Relating to partial stroke testing device configuration generally, in the device's 102 other configuration as a valve partial stroke testing device, the actuator 101 is operated to its' end of travel position, so determined by the adjustable stop travel 130 of the actuator 101 and to the position that it requires to be tested in for the partial stroke test.
- the device is configured as a partial stroke testing device when at the actuator's 101 end position, so determined by the actuator's 101 travel stop 130 and at the disengaged position of the device, the adjustable stop nut 110 is loosened enough and so adjusted on the extension rod threads 109 b that there is a gap 109 c formed between the index sleeve's outer face 106 a and the inner face 110 a of the adjustable stop nut 110 .
- the width of this gap 109 c determines the extent of the partial stroke.
- the adjustable stop nut 110 is so set that its double D profile aligns with the index sleeve's 106 double D profiled bore 106 e in the disengaged position of the device.
- the adjustable stop nut 110 is locked in this set position by set screws 111 on the extension rod threads 109 b .
- the partial stroke adjustment allows, by way of example only, twenty to thirty ( 20 to 30 ) degrees of rotation of the actuator's 101 output drive member 103 .
- the hand lever 131 is operated to turn the index sleeve 106 to clockwise extremity to engage the device 102 into testing mode.
- the index sleeve's 106 profiled double D bore 106 e is counter posed to the adjustable stop nut's 110 profile and the adjustable stop nut face 110 a now comes in contact with the index sleeve outer face 106 a which mechanically prevents the extension rod 109 and in turn the drive member 103 from moving any further.
- the actuator 101 has now performed a partial stroke.
- the actuator is operated back to its travel end position and the hand lever 131 is shifted to the device disengaged position which turns the index sleeve 106 back in alignment with the profile of the adjustable stop nut 110 , thereby posing no impedance to the full stroke motion of the extension rod 109 .
- the extension rod 109 and adjustable stop nut 110 Upon operation of the actuator 101 by application of pressure to its pneumatic cylinder to initiate counter clockwise rotation of actuator's output member 103 , the extension rod 109 and adjustable stop nut 110 is pulled in the direction of piston 105 movement and the adjustable stop nut 110 moves towards the index sleeve outer face 106 a for the distance set by the gap 109 c .
- the adjustable stop nut's 110 inner face 110 a comes in contact with index sleeve's 106 outer face 106 a as it cannot go through the index sleeve's double D profiled bore 106 e . This restricts the stroke of the linear motion member 112 and the stroke of the actuator to the extent of the gap 109 c set by the adjustable stop nut 110 on the extension rod 109 at the actuator's clockwise stroke end position.
- the adjustable stop nut 110 is so adjusted on the extension rod threads 109 b that it is in alignment with the index sleeve's double D profiled bore 106 e and its inner face 110 b just about bears on the index sleeve's outer face 106 a and is locked in position by set screws 111 .
- the extension rod 109 and adjustable stop nut 110 moves towards the index sleeve inner face 106 b for the distance set by the gap 109 d .
- the adjustable stop nut's 110 outer face 110 b comes in contact with index sleeve's 106 inner face 106 b as it cannot go through the index sleeve's double D profiled bore 106 e . This restricts the stroke of the linear motion member 112 and the stroke of the actuator to the extent of the gap 109 d set by the adjustable stop nut 110 on the extension rod 109 at the actuator's counter clockwise stroke end position.
- a tab 131 a with a hole on the hand lever 131 lines up with the safety stops 107 b or 107 c , providing a means of locking the hand lever 131 in either the PST engaged or disengaged positions of the device against unauthorized operation, by engaging a padlock 135 through the aligned holes in the safety stops 107 b or 107 c.
Abstract
Description
- Technical Field: The disclosure relates to the field of lockout devices for preventing the operation of a valve actuator and to the field of valve partial stroke test devices, which permit only a pre-determined extent of motion for the valve actuator.
- Safety equipment in industrial process plants with piping and valve installations typically include emergency shutdown valves (hereinafter, also “ESD valves”), blow off valves and bypass valves to prevent pressure build up in upstream or downstream sections. These valves normally remain open or closed but are actuated quickly to isolate sections of piping to stop further flow or bypass the flow, for emergency safety reasons. Actuation on ESD valves use fail-close actuator that is biased to close the valve, which is normally maintained in an open position by pneumatic pressure. These valves automatically close by the spring action or by reserve pneumatic supply upon loss of line air pressure due to a pressure system failure or in response to an emergency shutdown command signal. Regulations mandate periodic testing of such safety-instrumented systems to ensure the valve and all control elements are fully operational in an emergency.
- Partial stroke testing (hereinafter, also “PST”) devices fulfill this testing requirement without having to shut down the valve fully, which may disrupt or be detrimental to the normal process. A typical PST device is sandwiched between the valve and the actuator with a mechanical stop engaged to permit only a partial rotary motion of the valve operating member, or has a mechanical stop inserted into the translatory (meaning of, relating to, or involving uniform motion in one direction) path of the pneumatic actuator's piston rod, permitting only partial linear stroke.
- However, the operational safety also demands lockout devices that are required to prevent the actuator from operating under the fluid power during maintenance and repairs. This typically is met by an additional device and often suffers from being singular in its orientation and point of action, whereas the actuators are invariably provided with an over travel adjustment to compensate for the valve's true closing position. The challenge has been to combine all such requirements with a compensating mechanism to match the locking position of the actuator to the valve's true closed position, after having adjusted the actuator's travel stops.
- A solution to provide a combination device with its unique mechanism to compensate variability in the valve's true closing position and perform both of these said functions either by manual or remote operation, is the subject matter of this disclosure. Advantageous elaborations or embodiments of the disclosure are the objects of the present disclosure.
- Some examples of prior art on lockout and partial stroke valve test apparatus are shown in FIG. A, FIG. B and FIG. C.
- FIG. A shows a typical mechanical device that is fitted between the actuator and a rotary valve, the coupler shaft connects the valve's stem to the actuator's drive element. Rotary motion of the valve's drive member is restrained completely by a stopper bolt engaged in the device housing and the end of the stopper bolt locates into a hole or recess in the coupler shaft to lockout the rotary motion of the coupler and thereby the actuator and the valve. The device may further be locked out by engaging a lock pin through the housing and the stopper bolt and a padlock engaged into the lock pin. These device types are singular in their function as only a lockout apparatus and do not perform the partial stroke valve test.
- FIG. B shows an arrangement to engage a stopper pin in the path of the actuator's piston rod or its extension thereof, to restrict the linear motion of the piston rod in a partial stroke valve test device. The spring return stroke is restricted to a small predetermined extent when the stopper pin is inserted in the device's housing, as the end face of the piston rod contacts the stopper pin after the partial stroke and is mechanically restrained by the pin from further motion.
- FIG. C shows a partial stroke valve test device that is fitted between a rotary valve and the actuator with the device's coupler shaft adapted to connect the valve's stem to the actuator's drive member. The device typically has this coupler shaft keyed to a rotary member, segmented to provide a radial planar surface that bears on a cam stopper which when engaged, blocks the rotary motion of the segment and thereby the actuator and valve. The two extreme positions of the cam shaft select between the operation or test modes of the device. These device types are singular in their function as only a partial stroke valve test apparatus and do not lock out the actuator.
- The present disclosure relates to embodiments for a reliable and rugged mechanical device which when adapted to a fluid powered valve actuator, performs dual functions of a lockout and a partial stroke test device, capable of withstanding the full force of the pneumatic actuator. Configured as a lockout device, it prevents a pneumatic cylinder actuator's linear motion when the cylinder is pressurized.
- This disclosure pertains to the mechanisms on an exemplary embodiment of a single mechanical device that combines the functionality of a lockout device which prevents a valve pneumatic actuator from operating by fluid power in one mode and as a partial stroke valve test device in the other mode, which permits only a pre-determined extent of actuator's motion.
- The partial stroke test device finds most common use in testing for the anticipated response of the controls on a valve actuator in a fault insertion test. Such a device shall permit only a small movement of the valve stem so as not to adversely affect the pipeline flow and process parameters. This disclosure makes such a device easily field-configurable to a double as a lockout device too, that prevents motion of the actuator when so called for during maintenance.
- In one aspect as a lockout apparatus, the device has an activation mechanism to prevent linear motion of the actuator's piston rod and is set to lock the actuator and thereby the valve is locked in an open or closed position, normally at the stroke end. This can be further locked out in either position with a padlock to ensure the actuator on the process valve is not operated inadvertently or by unauthorized personnel.
- In another aspect as a partial stroke valve testing device, the mechanism enables easy field adjustment, which permits the actuator a pre-determined stroking before blocking further movement. The activation mechanism has further options of local operation by a manual lever or by a small short stroke pneumatic cylinder, for remote operation.
- One example of a lockout device in accordance with the present disclosure includes the device housing, two slides with linkages and pins, an actuating plunger, housing cover and an extension rod with an adjustable stopper nut. The device mounting adaptation bolts up on the actuator's housing. The extension rod is threaded at one end, which engages into one side of the actuator's guide block that is fixedly connected to the piston rod on its other side, integrating the extension rod coaxially with the pneumatic cylinder's piston rod. The other end of the extension rod is stepped down and threaded till its end beyond the step. An adjustable thimble nut is threaded on this end, forming a groove between the extension rod's step face and the nut's inner face.
- The extension rod fitted into the actuator's guide block at one end and the adjustable thimble nut on the other, passes through the device housing's bore unhindered in the normal operation of the actuator. The housing has two slides of thickness adapted to slide into the groove so formed by the extension rod's step and the thimble nut's faces. The two slides bear on the device housing on their rear face and their front faces bear on the actuating links and the housing cover. They move towards each other in the activated position or away from each other in de-activated position. This synchronized activating motion of these slides is accomplished by the linear movement of a plunger that is linked in an identical manner to each of these two slides through links and pinned joints. The sliding members have semi-circular cut-outs machined on their mating faces which envelope the step on the extension rod when the two slides are moved inwards into the locking position, by pulling outwards on the actuating plunger. In this locked position, the axial movement of the extension rod is constrained by the two slides that envelope the step and create an annular surface that the thimble nut bears on. The slides bear on the device housing and the thimble nut threaded on the extension rod bears on the slides, thereby blocking axial movement of the extension rod. Since the extension rod is coupled to the piston rod through a guide block in the actuator, the linear movement of the piston rod too is prevented and the actuator is locked out. Thus, this example of a lockout device in accordance with the present disclosure may be used to lock the pneumatic cylinder actuator in one of such several possible positions.
- To restore normal operation mode and upon pushing the plunger inwards into the device housing, the slides move away from each other and their profile clears the boundary of the extension rod and the adjusting thimble nut, thereby letting the extension rod with the thimble nut slide freely through the device housing.
- The same exemplary device configured as a partial stroke valve testing device has the thimble nut backed off on the extension rod threads to create a wide groove between the extension rod step face and the thimble nut inside face. The actuation of the plunger outwards from the device housing to effect the synchronized movement of the slides towards each other to engage the test mode or outwards to disengage the test mode remains the same as in the case of the lockout configuration of the device. However, now the extension rod can move axially under the influence of the pressure applied to the pneumatic cylinder of the actuator, to the extent of the width of the groove so formed by manual adjustment of the thimble nut. The stroke of the piston rod is now permitted for only the width of this groove thus providing an arrangement for partial stroking of the actuator.
- The plunger's position is further secured at its' two end positions by the provision of a safety stop to prevent inadvertent engagement of the operational and testing positions. A spring biased pin radially engages a collared nut threaded on the plunger, thereby preventing the plunger's movement unless the safety stop pin is selectively disengaged for the movement of the plunger for the test position or the operational position.
- A manual lever with linkages to operate the plunger is provided to effect the plunger movement effortlessly. A provision is made to lock this manual lever in its two extreme positions with a padlock, to prevent unauthorized operation of the device.
- A variant of this exemplary device to operate the lockout or the partial stroke test functionality by remote operation has the manual lever replaced by a small pneumatic cylinder that is adapted to fit and be coupled to the plunger. The device operation is effected by remote signal to a solenoid valve that pneumatically operates this actuation cylinder, which in turn moves the plunger in or out to accomplish the lock-unlock functions. A feedback sensor adapted to the mounting of the cylinder returns the confirmation signal of the device's position to the central control unit for further processing and sequencing.
- Another exemplary lockout device in accordance with the present disclosure includes the device housing, indexable sleeve with a double D profiled bore, an actuating lever, housing cover and an extension rod with an adjustable stop nut having a double D profile. The device mounting adaptation bolts up on the actuator's housing. The extension rod is threaded at one end suited to engage into one side of the actuator's guide block that is fixedly connected to the piston rod on its other side, integrating the extension rod coaxially with the pneumatic cylinder's piston rod. The other end of the extension rod is threaded for the required adjustment length and suited to a double D profiled adjustment nut.
- The extension rod fitted into the actuator's guide block at one end and the double D profiled adjustable stop nut on the other, passes through the device housing's bore unhindered in the normal operation of the actuator. The index sleeve has a double D profiled bore of the same profile as the profiled adjustable stop nut, but only of slightly bigger dimensions so as to just let the adjustment nut slide through the profiled bore, unhindered. The two flat faces of the profiled nut are set coplanar to the flat faces in the index sleeve's profiled bore, for the normal operation (full stroke of the actuator). The index sleeve can be rotated in the device housing but restricted to only 90 degree rotation by a spring biased plunger pin that indexes into either of the two slots machined radially and 90 degrees apart on the flange of the index sleeve.
- The indexation of the index sleeve from disengaged to the engaged position of the device is accomplished by turning on the hand lever that is fixedly attached to the outer end of index sleeve. When the index sleeve is turned clockwise to engage the device, the sleeve's double D bore profile gets offset to the adjustment nut's profile and this counter posed position prevents the adjustable stop nut from sliding through it. In this engaged position of the present exemplary device, the axial movement of the extension rod is constrained by the adjustment nut face bearing on the end face of the index sleeve. Since the extension rod is coupled to the piston rod through a guide block in the actuator, the linear movement of the piston rod too is prevented and the actuator is locked out. Thus, this exemplary lockout device in accordance with the present disclosure may be used to lock the pneumatic cylinder actuator in one of such several possible positions.
- To restore normal operation mode and upon turning the lever to rotate the index sleeve 90 degrees counter clockwise, the sleeve's profiled bore comes back into alignment with the adjustment nut profile, thereby letting the adjustment nut and extension rod slide freely through the sleeve and device housing.
- The same exemplary device when configured as a valve partial stroke testing device has the profiled adjustment nut backed off on the extension rod threads to create a gap between the index sleeve's outer face and the profiled adjustment nut's inside face. The actuation of a hand lever to effect the clockwise rotation of the index sleeve to engage the test mode or counter clockwise to disengage the test mode remains the same as in the case of the lockout configuration of the device. However, now the extension rod can move axially under the influence of the pressure applied to the pneumatic cylinder of the actuator, to the extent of the width of the gap so formed by manual adjustment of the adjustable stop nut. The stroke of the piston rod is now permitted for only the width of this gap thus providing an arrangement for partial stroking of the actuator.
- The hand lever's travel is limited to its' two end positions by the provision of safety stops on the housing cover, to prevent over travel of the index sleeve while effecting device engagement or disengagement for the testing or operational positions, respectively. A spring biased pin radially engages in the index slots on the index sleeve's flange, to enable accurate positioning of the index sleeve in its two end positions and to prevent any inadvertent operation of the hand lever. The index sleeve is locked in its end positions, unless the safety spring biased plunger pin is selectively disengaged for the rotation of the index sleeve for either of the test position or the operational positions.
- A hand lever to operate the device is provided to effortlessly effect the 90-degree rotation of the index sleeve. A provision is also made to positively lock this hand lever in its two extreme positions so determined by the safety stops on the housing cover, with a padlock to prevent unauthorized operation of the device.
- The embodiments may be better understood, and numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings. These drawings are used to illustrate only typical embodiments of this invention, and are not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
- FIG. A shows an exploded perspective view of a prior art coupling of an actuator and a rotary valve.
- FIG. B shows a prior art partial stroke valve test device.
- FIG. C shows a perspective view of a prior art partial stroke valve test device.
-
FIG. 1 shows a perspective view of an exemplary valve actuator fitted with the said combination device. -
FIG. 2 shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in unlocked position. -
FIG. 3 shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in locked position. -
FIG. 4 is the section view of an exemplary embodiment of the actuator and combination device mounted on a valve actuator, configured as a partial stroke valve testing device in a disengaged or operational position. -
FIG. 5 is the section view of an exemplary embodiment of the actuator and combination device mounted on a valve actuator, configured as a partial stroke valve testing device in an engaged or testing position. -
FIG. 6 shows a section view of an exemplary embodiment of the fitment of the extension rod of the device on to the guide block of the pneumatic actuator. -
FIG. 7 shows the section view of an exemplary embodiment of the device housing and the locking elements engaged into the extension rod in locked out position. -
FIG. 8 is the sectional perspective view of an exemplary embodiment of the device with the cover removed, showing the slides and linkages housed inside the device housing and the operating lever linked to the plunger that activates the slides movement. -
FIG. 9 shows the section view of an exemplary embodiment of the device housing with cover and the spring biased pin retaining the collar nut and thereby the plunger, in its indexed position. -
FIG. 10 is the perspective view of an exemplary embodiment of the device with the actuating handle locked with a padlock to prevent inadvertent or unauthorized operation of the device. -
FIG. 11 is the elevation view of an exemplary embodiment of the device without the cover showing the positions of the slides and links within the housing, in its unlocked position. -
FIG. 12 is the elevation view of an exemplary embodiment of the device without the cover showing the positions of the slides and links within the housing, in its locked position. -
FIG. 13 is the section view of an exemplary embodiment of the device set to partial stroke valve testing mode by the positioning of the thimble nut and engaging of the slides to permit a predetermined linear movement of the extension rod. -
FIG. 14 shows an exemplary embodiment of the adaptation of the device to remote operation, by replacement of the handle operating mechanism with a short stroke pneumatic cylinder operated by a solenoid valve. -
FIG. 15A shows a perspective view of a valve spring return actuator fitted with another exemplary combination device. -
FIG. 15B shows a perspective view of a valve direct acting actuator fitted with an exemplary combination device. -
FIG. 15C shows a section view of a valve actuator fitted with an exemplary combination device. -
FIG. 16A shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator at one end of the actuator's travel, configured as a lockout device in unlocked position. -
FIG. 16B shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator at mid position of actuator's travel, configured as a lockout device in unlocked position. -
FIG. 16C shows a section view of an exemplary embodiment of the combination device mounted on a valve actuator at the other end of actuator's travel, configured as a lockout device in unlocked position. -
FIG. 16D shows a section view of an exemplary embodiment of the combination device mounted on a variant configuration of a valve actuator at one end of its travel, configured as a partial stroke test device in engaged position. -
FIG. 17A is the section view of an exemplary embodiment of the combination device, configured as a valve partial stroke testing device in a disengaged or operational position. -
FIG. 17B is the section view of an exemplary embodiment of the combination device, configured as a valve partial stroke testing device in engaged or test position. -
FIG. 17C is the part section side view of an exemplary embodiment of the combination device showing the indexed position locking by the spring biased plunger pin, in disengaged position of the device. The view also shows the adjustable stop nut profile in alignment with respect to the index sleeve's profiled bore. -
FIG. 17D is the part section side view of an exemplary embodiment of the combination device showing the other indexed position locking by the spring biased plunger pin, in engaged or test position of the device. The view also shows the adjustable stop nut profile counter posed with respect to the index sleeve's profiled bore. -
FIG. 17E is an exploded view of an exemplary embodiment of the combination device showing the parts comprising of the device, excluding the extension rod. -
FIG. 17F is an end view taken fromFIG. 17A . -
FIG. 17G is an end view taken fromFIG. 17B . -
FIG. 18A is the perspective view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in an engaged position at one end of the actuator's end position. -
FIG. 18B is the perspective view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a lockout device in an engaged position at the other end of the actuator's travel position. -
FIG. 18C is the perspective view of an exemplary embodiment of the combination device with the actuating handle locked with a padlock to prevent inadvertent or unauthorized operation of the device. -
FIG. 19A is the perspective view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device in disengaged position at one end of the actuator's travel position. -
FIG. 19B is the perspective view of an exemplary embodiment of the combination mounted on a valve actuator, configured as a partial stroke test device in the engaged position at one end of the actuator's travel position. -
FIG. 19C is the perspective partial sectioned view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device in disengaged position at the other end of the actuator's travel position. -
FIG. 19D is the perspective partial sectioned view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device showing the set partial stroke. -
FIG. 19E is the perspective partial sectioned view of an exemplary embodiment of the combination device mounted on a valve actuator, configured as a partial stroke test device in the engaged position at the other end of the actuator's travel position. - The description that follows includes exemplary apparatus, methods, techniques, and instruction sequences that embody techniques of the inventive subject matter. However, it is understood that the described embodiments may be practiced without these specific details.
- An exemplary embodiment of an
actuator 1 of scotch yoke type (e.g., such as a fluid powered cylinder actuator) on which an exemplary embodiment of a lockout and partial stroketest combination device 2, in accordance with the present disclosure, may be fitted is depicted inFIGS. 1 through 5 . The disclosed improvements can be implemented into other types of actuators 1 (by way of example only, and not limited to, linear actuators). Theexemplary actuator 1 is used for turning the flow control member of a quarter turn valve (not shown). Theactuator 1 depicted here converts the linear motion of thepiston 5 on application of fluid pressure on either side of thepiston 5 to rotary motion of the actuator's 1 output drive member or drive element, namelyyoke 3, by the scotch yoke mechanism of thisexemplary actuator 1. It may be understood that theactuator 1 could be of rack and pinion style or a diaphragm style and so forth. It must also be understood that a lockout and partial stroketest combination device 2 in accordance with this disclosure may be used in combination with other cylinder actuator designs than those described herein, for example, on a linear valve actuator (not shown) and may also be used in combination with cylinder actuators (not shown) that are not employed for controlling the flow control member of a valve. -
FIG. 2 andFIG. 3 show thedevice housing 2 a integrated with the adaptation to (or, adapted to) mount on theactuator housing 1 a to receive and align thedevice 2 to the axis of thelinear motion member 12 of theactuator 1, namely thecylinder piston rod 4. Theextension rod 9 also forms thelinear motion member 12, coaxial to thepiston rod 4, coupled to theguide block 8 of theactuator 1 by threading and in the operation mode, theextension rod 9 freely passes through the lockout and partial stroke testcombination device housing 2 a, through the housing bore 2 b, unhindered throughout the entire stroke of the actuator's 1guide block 8. - Referring to
FIG. 5 andFIG. 6 , the rotary motion of theyoke 3 is restrained by the actuator's 1 integral and adjustable travel stops or stopbolt 30 in theactuator 1. In the operation mode ofFIG. 4 , the restraining members of the device, namely theslides 13, are in their extreme outward retracted position (as radially retracted away from the linear motion of the extension rod 9) and do not impede the motion of theextension rod 9. Theextension rod 9 is threaded at one end (9 a) which engages and locks into oneside 8 a of the actuator's 1guide block 8; theguide block 8 is also fixedly connected to thepiston rod 4 on theother side 8 b of theguide block 8, integrating theextension rod 9 coaxially with the pneumatic cylinder'spiston rod 4. Theother end 9 b of theextension rod 9 is stepped down and threaded beyond. A thimble nut orfastener 10 is threaded on theother end 9 b of theextension rod 9 for adjustment and positioning, forming a groove (or section ofextension rod 9 having an outer diameter less than the outer diameter of the thimble nut 10) between the rod's 9step face 6 and the thimble nut's 10inner face 7. - Referring to
FIG. 7 ,FIG. 8 andFIG. 12 , theslides 13 are housed symmetrically within and guided byplanes 18 at the top and bottom in thedevice housing 2 a to enable them to slide in a unilateral manner bylinks 17 which are hinged to theslides 13 bypins 16 on oneextremity 17 a and to theplunger head 23 on theirother extremity 17 b. Theplunger head 23 is guided in thedevice housing 2 a and theplunger head 23 is constrained to move only in transverse direction to theslides 13 by the guidingplanes 19 of thehousing 2 a. Theslides 13 bear on the recessedface 14 of thedevice housing 2 a (seeFIG. 7 ). - Referring to
FIG. 9 ,FIG. 10 andFIG. 11 , ahousing cover 20 retains the internal parts within thehousing 2 a without hindering their motion. Atubular cover 44 as shown inFIG. 10 protects theextension rod 9. The extendingpart 23 a of theplunger 23 from thehousing 2 a is threaded to receive anadjustable collar nut 24 which is restrained by a spring biased safety pin orsafety device 22, thread into an adaptedextension 21 of thehousing cover 20. Theextreme end 23 a of theplunger 23 is adapted to receive apin 29 that engages with thehandle 31 forming ahinge 31 a (seeFIG. 10 ). Thehandle 31 is pivoted at its end by apin 28 on a plate link orlink plate 27 which in turn is hinged to afixity 25 on thehousing 2 a by apin 28 a. - Releasing the
safety pin 22 by pulling on the springbiased pin ring 32 outward to clear thecollar nut 24 and actuation of thehandle 31 upwards, lifts theplunger 23 which in turn, through thelinks 17 drives theslides 13 uniformly towards each other until their leading faces or ends 34 bear against each other. In this closed position (see, e.g.,FIG. 12 ), theslides 13 form a planar surface orthogonal to the extension rod's 9 axis and the semi-circular cut-outs 33 on theslides 13 form ahole 33 a in the aforementioned closed position. -
FIG. 3 andFIG. 7 show thedevice 2 in its lockout configuration and engaged in the locked position. Theactuator 1 is operated to its' end of travel position, so determined by the adjustable travel stops or stopbolts 30 of theactuator 1 and in the direction that it needs to be locked in. - Referring to
FIG. 10 andFIG. 11 , thehandle 31 is moved to its upper extreme position upon releasing thesafety pin 22 by pulling on thepin ring 32 to enable thecollar nut 24 and theplunger 23 to traverse outward from thehousing 2 a. Upon actuating thehandle 31 to the locked position inFIG. 12 , theslides 13 contact each other at their leading faces or ends 34 and close on the stepped downsection 9 b of theextension rod 9 with the semi-circular cut-outs 33 forming ahole 33 a encompassing the extension rod'ssection 9 b between thestep face 6 and the thimble nut'sinner face 7. Releasing thepin ring 32 returns thesafety pin 22 to below thecollar 24 and retains theplunger 23 and thehandle 31 in this locked position. - Referring again to
FIG. 6 andFIG. 7 , thethimble nut 10 is now so adjusted to let theinner face 7 of thethimble nut 10 just about to bear on the slides' 13 front faces 15. Aset screw 11 locks the thimble nut's 10 position on theextension rod 9. - Application of pressure to the actuator's 1 cylinder in the said locked position results in the
thimble nut 10 loading on the slides' 13 faces 15 and thereby prevents theextension rod 9, theguide block 8 and in turn theyoke 3 from moving. Theactuator 1 is thus locked out in this position. To unlock, thehandle 31 is shifted to an extreme down position which translates theslides 13 through thelinks 17 to retract theslides 13 to their end positions within thehousing 2 a, wherein theslides 13 are retracted away fromlinear motion member 12, clearing thethimble nut 10 and theextension rod 9 completely, thereby posing no impedance to the motion of theextension rod 9. - Referring to
FIG. 10 ,FIG. 11 andFIG. 12 , aplate link 27 having twoholes slot 26 in theextension 31 b of thehandle 31, provide a means of locking thehandle 31 against unauthorized operation, in its two said positions by engaging apadlock 35 through the alignedholes - In the exemplary device's 2 other configuration as a partial stroke valve testing device, the
actuator 1 is operated to its' end of travel position, so determined by the adjustable travel stops 30 of theactuator 1 and to the position that it requires to be tested in for the partial stroke test. - Referring to
FIG. 12 andFIG. 13 , thehandle 31 is operated upward to engage thedevice 2 into testing mode. Thethimble nut 10 on theextension rod 9 is loosened and so adjusted that there is agap 9 c formed between the slides' 13outer faces 15 and theinner face 7 of thethimble nut 10. The width of thisgap 9 c determines the extent of the partial stroke. The partial stroke adjustment allows, by way of example only, twenty to thirty (20 to 30) degrees of rotation of the actuator's 1output drive member 3. - In the test mode, application of pressure to the actuator's 1 cylinder to operate the
actuator 1 counter to the said travel end position, results in thepiston rod 4, theextension rod 9 and thus thethimble nut 10 to move towards the slide faces 15, to the extent of the saidgap 9 c between theslides 13 and thethimble nut face 7. Thethimble nut face 7 now comes in contact with theslide face 15 and thereby mechanically prevents theextension rod 9 and in turn thedrive member 3 from moving any further. Theactuator 1 has now performed a partial stroke. To restore operation mode, thehandle 31 is shifted to extreme down position which translates theslides 13 through thelinks 17 to retract theslides 13 to their end positions within thehousing 2 a, wherein theslides 13 are retracted away from thelinear motion member 12, clearing thethimble nut 10 and theextension rod 9 completely, thereby posing no impedance to the motion of theextension rod 9. - Referring to
FIG. 10 ,FIG. 11 andFIG. 12 , aplate link 27 having twoholes slot 26 in theextension 31 b of thehandle 31, provide a means of locking thehandle 31 against unauthorized operation, in its two said positions by engaging apadlock 35 through the alignedholes -
FIG. 14 shows an alternative exemplary embodiment of thedevice 2 with optional remote actuation, wherein themanual actuation handle 31 and associated parts are replaced by apneumatic cylinder 42. In this exemplary embodiment, apneumatic cylinder 42 is mounted on abracket 39 that aligns thecylinder 42 coaxially with theplunger 23 and thepiston rod 41 of thepneumatic cylinder 42 is coupled to theplunger 23 with acoupler 40 andpin 38. Thepneumatic cylinder 42 is operated by asolenoid valve 45, the power to which is controlled remotely from the central control unit (not illustrated). This arrangement allows the partial stroke valve test to be performed remotely once thedevice 2 has been configured for the purpose.Sensors 43 on thebracket 39 provide a feedback signal to the central control unit for the confirmation of the actuation position, and to further engage or disengage the test mode. - A scotch yoke type of actuator 101 (e.g., such as a fluid powered cylinder actuator) on which another exemplary embodiment of a lockout and partial stroke
test combination device 102, in accordance with the present disclosure, may be fitted is depicted inFIGS. 15A through 15C . Theexemplary actuator 101 is used for turning the flow control member of a quarter turn valve (not shown). Theactuator 101 depicted here converts the linear motion of thepiston 105 on application of fluid pressure on either side of thepiston 105 to rotary motion of the actuator's 101 output drive member or drive element, namelyyoke 103, by the scotch yoke mechanism of thisexemplary actuator 101. It may be understood that theactuator 101 could be of rack and pinion style or a diaphragm style and so forth. It must also be understood that a lockout and partial stroketest combination device 102 in accordance with this disclosure may be used in combination with other cylinder actuator designs than those described herein, for example, on a linear valve actuator (not shown) and may also be used in combination with cylinder actuators (not shown) that are not employed for controlling the flow control member of a valve. -
FIG. 16A andFIG. 16D show thedevice housing 102 a integrated with the adaptation to (or adapted to) mount on theactuator housing 101 a to receive and align thedevice 102 to the axis of thelinear motion member 112 of theactuator 101, namely thecylinder piston rod 104. Theextension rod 109 also forms thelinear motion member 112, coaxial to thepiston rod 104, coupled to the guide block 108 of theactuator 101 by threading and in the operation mode, theextension rod 109 freely passes through the index sleeve's 106 double D profiled bore 106 e, unhindered throughout the entire stroke of the actuator's 101guide block 108. - Relating to construction and operation generally and referring to
FIG. 16A ,FIG. 16B ,FIG. 16C andFIG. 16D , the actuator is seen progressively from its clockwise end position to mid travel position and to its counter clockwise end position with the rotary motion of theyoke 103 limited by the actuator's 101 integral and adjustable travel stops or stroke stopbolts 130 in theactuator housing 101 a. Theextension rod 109 is threaded at oneend 109 a which engages and locks into female threads on oneside 108 a of the actuator's 101guide block 108; theguide block 108 is also fixedly connected to thepiston rod 104 on theother side 108 b of theguide block 108, integrating theextension rod 109 coaxially with the pneumatic cylinder'spiston rod 104. Theother end 109 b of theextension rod 109 is threaded to receive a double D profiled adjustable stop nut orfastener 110 on theextension rod 109 for the partial stroke adjustment and positioning. Theadjustable stop nut 110 too is of a double D profile but is of slightly smaller dimensions than the profiled bore 106 e in theindex sleeve 106, permitting theadjustable stop nut 110 to slide through the index sleeve bore 106 e. - In the operation mode, as seen in
FIG. 17A ,FIG. 17C andFIG. 19A , the stroke restraining member of the device, namely theindex sleeve 106, is in its extreme counter clockwise position so determined by the springbiased indexing pin 122 locating into theslot 106 j on the index sleeve's 106flange 106 f. In this said position, theadjustment nut 110 is so set and locked on the extension rod's 109threads 109 b by aset screws 111 that its double D profile aligns with the index sleeve's 106 double D profiled bore 106 e thereby the motion of theextension rod 109 and theadjustment nut 110 through theindex sleeve 106 it is not impeded. - Referring to
FIG. 17A andFIG. 17B , theindex sleeve 106 is located coaxially within thehousing 102 a by sliding fit of theindex sleeve 106 into thebore 102 b of thehousing 102 a. Theinner face 106 c of theindex sleeve flange 106 f bears on the housing's 102 arear flange face 102 c. Thehousing cover 107 envelopes theindex sleeve flange 106 f, with the inner recessedface 107 a of thecover 107 bearing on the index sleeve flange's 106 fouter face 106 d and thecover 107 is bolted on to the housing's 102 a rear flange bybolts 146. The index sleeve is thus free to only rotate within thehousing 102 a and thehousing cover 107 but constrained from axial movement by the housingend flange face 102 c and the housing cover's 107 inside recessedface 107 a which bear on the two faces of the index sleeve flange's 106 f faces 106 c and 106 d, respectively. - Referring to
FIG. 17A ,FIG. 17B andFIG. 17C , ahousing cover 107 retains theindex sleeve 106 within thehousing 102 a without hindering the index sleeve's 106 rotary motion within thehousing 102 a. Atubular cover 144 as shown inFIG. 16E is threaded on the index sleeve's threadedend 106 g to protect theextension rod 109 and theadjustable stop nut 110. A spring biasedindexing pin 122 is thread radially into thehousing cover 107 and the pin locates into theradial slot 106 j when the device is disengaged and into theslot 106 k when theindex sleeve 106 is turned clockwise to engage the device. Theindex sleeve 106 has a threadedhole 106 h that receives thehandle 131 that is threaded on its one end and is locked on to theindex sleeve 106 by alock nut 147. - Referring
FIG. 17C andFIG. 17D , releasing the spring biased safety pin orsafety device 122 by pulling on thepin ring 132 outward to clear theslot 106 j and actuation of thehand lever 131 upwards, turns theindex sleeve 106 clockwise. On release of the spring biasedindexing pin ring 132 while rotating theindex sleeve 106 clockwise by thehandle 131, the pin locates into theradial slot 106 k on the index sleeve'sflange 106 f and locks theindex sleeve 106 in the device's thus engaged position. In this engaged position (seeFIG. 17D andFIG. 19B ), theouter face 106 a of theindex sleeve 106 forms a planar surface orthogonal to the extension rod's 109 axis and is in direct path of the adjustable stop nut's 110 translatory motion. - Relating to the locking device configuration generally,
FIG. 16D andFIG. 18A show thedevice 102 in its lockout configuration and engaged to the locked position. Prior to engaging the device, theactuator 101 is operated to its' end of travel position, so determined by the adjustable stop travel stops 130 of theactuator 101 in the direction that it needs to be locked in. - Referring again to
FIG. 18A andFIG. 18B , the device is configured as a locking device when at the actuator's 101 end position, so determined by the actuator's 101 travel stops or stroke stopbolts adjustable stop nut 110 is so adjusted on theextension rod threads 109 b to let theinner face 110 a of theadjustable stop nut 110 just about to bear on theindex sleeve 106outer face 106 a. Theadjustable stop nut 110 is set at this position on theextension rod threads 109 b such that the double D profile of theadjustable stop nut 110 aligns with the index sleeve's 106 double D bore 106 e. Aset screw 111 locks the adjustable stop nut's 110 position on theextension rod 109. - Relating to engage-disengage lock generally and referring
FIG. 18A , engaging the device so configured as a locking device is effected by operating on thehand lever 131 to rotate theindex sleeve 106 to its clockwise extremity upon pulling on the springbiased pin ring 132 to disengage the springbiased pin 122. Application of pressure to the actuator 101 cylinder in the said locked position results in theadjustable stop nut 110 loading on the index sleeve's 106outer face 106 a, thereby preventing theextension rod 109, theguide block 108 and in turn theyoke 103 from moving. Theactuator 101 is thus locked out in this position. To unlock, the springbiased pin 122 is released and handle 131 is shifted to turn theindex sleeve 106 counter clockwise to its extremity position determined by the engagement of the springbiased pin 122 into theradial slot 106 j on theindex sleeve flange 106 f, to disengage the device whereby the index sleeve's 106 profiled bore 106 e realigns with the double D profiledadjustable stop nut 110 on theextension rod 109, posing no impedance to the motion of theextension rod 109 through theindex sleeve 106 and thehousing 102 a. - Relating to locking clockwise generally, referring to
FIG. 16A ,FIG. 17A ,FIG. 17C andFIG. 18A , when the actuator is at its clockwise stroke end, so determined by the clockwise travel stop bolt or adjustable travel stop 130 a on theactuator housing 101 a, and when thehand lever 131 is moved to turn theindex sleeve 106 to its clockwise extremity, upon releasing thesafety pin 122 by pulling on thepin ring 132 to thus engaged position of the device, the index sleeve's 106 double D profiled bore 106 e goes out of alignment and is counter posed with the adjustable stop nut's 110 double D profile. The adjustable stop nut's 110inner face 110 a can now only bear upon the index sleeve's 106outer face 106 a and cannot go through the index sleeve's double D profiled bore 106 e. This locks up the actuator in its clockwise stroke end position. - Relating to locking counterclockwise generally, referring to
FIG. 16A ,FIG. 17A ,FIG. 17C andFIG. 18B , when the actuator is at its counter clockwise stroke end, so determined by the counter clockwise travel stop bolt or adjustable travel stop 130 b on theactuator housing 101 a, and in this position when thehand lever 131 is moved upward to turn theindex sleeve 106 to its clockwise extremity upon releasing thesafety pin 122 by pulling on thepin ring 132 to thus engaged position of the device, the index sleeve's 106 double D profiled bore 106 e goes out of alignment and is counter posed with the adjustable stop nut's 110 double D profile. The adjustable stop nut's 110outer face 110 b can now only bear upon the index sleeve's 106inner face 106 b and cannot go through the index sleeve's double D profiled bore 106 e. This locks up the actuator in its counter clockwise stroke end position. - Relating to a padlock generally and referring to
FIG. 18B andFIG. 18C , atab 131 a with a hole on thehand lever 131 lines up with the safety stops 107 b or 107 c with similar hole, providing a means of locking thehand lever 131 in either the engaged or disengaged positions of the device, against unauthorized operation by engaging apadlock 135 through the aligned holes in the safety stops 107 b or 107 c. - Relating to partial stroke testing device configuration generally, in the device's 102 other configuration as a valve partial stroke testing device, the
actuator 101 is operated to its' end of travel position, so determined by theadjustable stop travel 130 of theactuator 101 and to the position that it requires to be tested in for the partial stroke test. - Referring to
FIG. 17B ,FIG. 19A andFIG. 19B , the device is configured as a partial stroke testing device when at the actuator's 101 end position, so determined by the actuator's 101travel stop 130 and at the disengaged position of the device, theadjustable stop nut 110 is loosened enough and so adjusted on theextension rod threads 109 b that there is agap 109 c formed between the index sleeve'souter face 106 a and theinner face 110 a of theadjustable stop nut 110. The width of thisgap 109 c determines the extent of the partial stroke. Theadjustable stop nut 110 is so set that its double D profile aligns with the index sleeve's 106 double D profiled bore 106 e in the disengaged position of the device. Theadjustable stop nut 110 is locked in this set position byset screws 111 on theextension rod threads 109 b. The partial stroke adjustment allows, by way of example only, twenty to thirty (20 to 30) degrees of rotation of the actuator's 101output drive member 103. Thehand lever 131 is operated to turn theindex sleeve 106 to clockwise extremity to engage thedevice 102 into testing mode. - Relating to engage-disengage generally and referring
FIG. 16A ,FIG. 17B ,FIG. 19A andFIG. 19B , in the test mode, so selected by shifting the device to its engaged position, application of pressure to the actuator's 101 cylinder to operate theactuator 101 counter to its said travel end position, results in thepiston rod 104, theextension rod 109 and thus theadjustable stop nut 110 to move towards the index sleeve'souter face 106 a, to the extent of the saidgap 109 c between theface 106 a and the adjustable stop nut'sinner face 110 a. With the device turned to its engaged position, the index sleeve's 106 profiled double D bore 106 e is counter posed to the adjustable stop nut's 110 profile and the adjustablestop nut face 110 a now comes in contact with the index sleeveouter face 106 a which mechanically prevents theextension rod 109 and in turn thedrive member 103 from moving any further. Theactuator 101 has now performed a partial stroke. To restore operation mode, the actuator is operated back to its travel end position and thehand lever 131 is shifted to the device disengaged position which turns theindex sleeve 106 back in alignment with the profile of theadjustable stop nut 110, thereby posing no impedance to the full stroke motion of theextension rod 109. - Relating to partial stroke test at actuator's clockwise end generally, referring to
FIG. 16A ,FIG. 19A andFIG. 19B , with the actuator at its clockwise stroke end, so determined by the clockwisetravel stop bolt 130 a on theactuator housing 101 a, and when thehand lever 131 is moved to turn theindex sleeve 106 to its clockwise extremity, upon releasing thesafety pin 122 by pulling on thepin ring 132 to thus engaged position of the device, the index sleeve's 106 double D profiled bore 106 e goes out of alignment and is counter posed with the adjustable stop nut's 110 double D profile. Upon operation of theactuator 101 by application of pressure to its pneumatic cylinder to initiate counter clockwise rotation of actuator'soutput member 103, theextension rod 109 andadjustable stop nut 110 is pulled in the direction ofpiston 105 movement and theadjustable stop nut 110 moves towards the index sleeveouter face 106 a for the distance set by thegap 109 c. The adjustable stop nut's 110inner face 110 a comes in contact with index sleeve's 106outer face 106 a as it cannot go through the index sleeve's double D profiled bore 106 e. This restricts the stroke of thelinear motion member 112 and the stroke of the actuator to the extent of thegap 109 c set by theadjustable stop nut 110 on theextension rod 109 at the actuator's clockwise stroke end position. - Relating to partial stroke test at actuator's counterclockwise end generally, referring to
FIG. 16A ,FIG. 19C ,FIG. 19D andFIG. 19E , with the actuator at its clockwise stroke end, so determined by the CWtravel stop bolt 130 a on theactuator housing 101 a and the device in disengaged position, theadjustable stop nut 110 is so adjusted on theextension rod threads 109 b that it is in alignment with the index sleeve's double D profiled bore 106 e and itsinner face 110 b just about bears on the index sleeve'souter face 106 a and is locked in position byset screws 111. When the actuator is operated to its counter clockwise end position so determined by the actuator'stravel stop bolt 130 b, there would form agap 109 d between the index sleeveinner face 106 b and the adjustable stop nutouter face 110 b, seeFIG. 19D . At the actuator's counter clockwise end position, the device is engaged by thehand lever 131 moved to turn theindex sleeve 106 to its clockwise extremity, upon releasing thesafety pin 122 by pulling on thepin ring 132 to thus engaged position of the device thereby the index sleeve's 106 double D profiled bore 106 e goes out of alignment and is counter posed with the adjustable stop nut's 110 double D profile. Upon operation of theactuator 101 to initiate clockwise rotation of actuator'soutput member 103, theextension rod 109 andadjustable stop nut 110 moves towards the index sleeveinner face 106 b for the distance set by thegap 109 d. The adjustable stop nut's 110outer face 110 b comes in contact with index sleeve's 106inner face 106 b as it cannot go through the index sleeve's double D profiled bore 106 e. This restricts the stroke of thelinear motion member 112 and the stroke of the actuator to the extent of thegap 109 d set by theadjustable stop nut 110 on theextension rod 109 at the actuator's counter clockwise stroke end position. - Relating to partial stroke test padlocking generally and referring to
FIGS. 18B and 18C , atab 131 a with a hole on thehand lever 131 lines up with the safety stops 107 b or 107 c, providing a means of locking thehand lever 131 in either the PST engaged or disengaged positions of the device against unauthorized operation, by engaging apadlock 135 through the aligned holes in the safety stops 107 b or 107 c. - It is understood that the present disclosure is not limited to the particular applications and embodiments described and illustrated herein, but covers all such variations thereof as come within the scope of the claims. While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions and improvements are possible.
- Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter.
Claims (23)
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US15/225,515 US10378562B2 (en) | 2015-07-30 | 2016-08-01 | Combination device for lockout and partial stroke test of valve actuators |
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US15/225,515 US10378562B2 (en) | 2015-07-30 | 2016-08-01 | Combination device for lockout and partial stroke test of valve actuators |
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US10378562B2 US10378562B2 (en) | 2019-08-13 |
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US20220403949A1 (en) * | 2019-11-25 | 2022-12-22 | Emerson Process Management Regulator Technologies, Inc. | Scotch Yoke Actuator |
US20230336066A1 (en) * | 2022-04-15 | 2023-10-19 | Steven William Cragar | Spiral Magnetic Engine |
US11976745B2 (en) * | 2019-11-25 | 2024-05-07 | Emerson Process Management Regulator Technologies, Inc. | Scotch yoke actuator |
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ES2724908B2 (en) * | 2019-06-04 | 2020-06-04 | Actreg S A U | DEVICE FOR PARTIAL RACE TEST, LOCKING AND AUTOMATIC RUN ADJUSTMENT IN EMERGENCY VALVE ACTUATORS |
CN114112347B (en) * | 2021-11-18 | 2024-04-09 | 庆安集团有限公司 | Small-size modular constant force loading life test device |
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- 2016-08-01 WO PCT/US2016/045039 patent/WO2017020044A1/en active Application Filing
- 2016-08-01 CA CA2993437A patent/CA2993437C/en active Active
- 2016-08-01 US US15/225,515 patent/US10378562B2/en active Active
- 2016-08-01 BR BR112018001912-7A patent/BR112018001912B1/en active IP Right Grant
- 2016-08-01 EP EP16756830.2A patent/EP3329163B1/en active Active
- 2016-08-01 CN CN201680055930.4A patent/CN108138986B/en active Active
- 2016-08-01 MX MX2018001220A patent/MX2018001220A/en unknown
- 2016-08-01 AU AU2016298435A patent/AU2016298435B2/en active Active
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2018
- 2018-02-09 ZA ZA2018/00881A patent/ZA201800881B/en unknown
- 2018-11-30 HK HK18115371.7A patent/HK1256306A1/en unknown
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
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US20150345645A1 (en) * | 2014-05-30 | 2015-12-03 | Applied Materials, Inc. | Valve with adjustable hard stop |
US9982786B2 (en) * | 2014-05-30 | 2018-05-29 | Applied Materials, Inc. | Valve with adjustable hard stop |
US20220403949A1 (en) * | 2019-11-25 | 2022-12-22 | Emerson Process Management Regulator Technologies, Inc. | Scotch Yoke Actuator |
US11976745B2 (en) * | 2019-11-25 | 2024-05-07 | Emerson Process Management Regulator Technologies, Inc. | Scotch yoke actuator |
US20230336066A1 (en) * | 2022-04-15 | 2023-10-19 | Steven William Cragar | Spiral Magnetic Engine |
Also Published As
Publication number | Publication date |
---|---|
EP3329163B1 (en) | 2020-10-21 |
HK1256306A1 (en) | 2019-09-20 |
CN108138986B (en) | 2020-11-03 |
CN108138986A (en) | 2018-06-08 |
CA2993437C (en) | 2023-10-17 |
BR112018001912B1 (en) | 2022-04-19 |
WO2017020044A1 (en) | 2017-02-02 |
MX2018001220A (en) | 2018-06-19 |
EP3329163A1 (en) | 2018-06-06 |
AU2016298435B2 (en) | 2021-01-07 |
CA2993437A1 (en) | 2017-02-02 |
AU2016298435A1 (en) | 2018-02-15 |
ZA201800881B (en) | 2019-07-31 |
BR112018001912A2 (en) | 2018-09-25 |
US10378562B2 (en) | 2019-08-13 |
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